The expression is
.
Apply trigonometric identity :
.


Equate the
and
terms on each side.
and 




.
Substitute
in
.

.
Substitute
and
in
.
.
The integral is
.
Substitute
.


Consider
.
Apply derivative on each side with respect to
.


.
Substitute
and
in
.

Apply formula :
.

Substitute
.

.
The values of
and
and
.